Reduced area imaging device incorporated within endoscopic devices

ABSTRACT

A reduced area imaging device is provided for use in medical or dental instruments such as an endoscope. The imaging device is provided in various configurations, and connections between the imaging device elements and a video display may be achieved by wired or wireless connections. A connector assembly located near the imaging device interconnects the imaging device to an image/power cable extending through the endoscope. The connector provides strain relief and stabilization for electrically interconnecting the imager to the cable. The connector also serves as the structure for anchoring the distal ends of steering wires extending through the body of the endoscopic device. The connector includes a strain relief member mounted over a body of the connector. The connector allows a steering wire capability without enlarging the profile of the distal tip of the endoscopic device.

This is a continuation of application Ser. No. 13/732,908 filed Jan. 2,2013, which was a continuation of U.S. Ser. No. 12/889,287 filed on Sep.23, 2010, and entitled “Reduced Area Imaging Device Incorporated WithinWireless Endoscopic Devices”, which is a continuation-in-part of U.S.Ser. No. 11/245,960, filed on Oct. 6, 2005, and entitled “Reduced AreaImaging Device Incorporated Within Wireless Endoscopic Devices”, whichis a continuation of U.S. patent application Ser. No. 09/929,531, filedon Aug. 13, 2001, and entitled “Reduced Area Imaging Device IncorporatedWithin Wireless Endoscopic Devices”, now U.S. Pat. No. 7,030,904 whichis a continuation-in-part of U.S. Ser. No. 09/496,312 filed on Feb. 1,2000, and entitled “Reduced Area Imaging Devices”, now U.S. Pat. No.6,275,255, which is a continuation of U.S. Ser. No. 09/175,685 filedOct. 20, 1998 entitled “Reduced Area Imaging Devices”, now U.S. Pat. No.6,043,839, which is a continuation-in-part of U.S. Ser. No. 08/944,322,filed Oct. 6, 1997, and entitled “Reduced Area Imaging DevicesIncorporated Within Surgical Instruments”, now U.S. Pat. No. 5,929,901.application Ser. No. 13/732,908, 12/889,287, 11/245,960, 09/929,531,09/496,312, 09/175,685 and 08/944,322 are hereby incorporated byreference in their entireties.

FIELD OF THE INVENTION

This invention relates to solid state image sensors incorporated withinwireless endoscopes, and more particularly, to solid state image sensorswhich are incorporated within wireless endoscopes that wirelesslytransmit video images for viewing.

BACKGROUND OF THE INVENTION

In recent years, endoscopic surgery has become the accepted standard forconducting many types of surgical procedures, both in the medical anddental arenas. The availability of imaging devices enabling a surgeon ordentist to view a particular surgical area through a small diameterendoscope which is introduced into small cavities or openings in thebody results in much less patient trauma as well as many otheradvantages.

In many hospitals, the rod lens endoscope is still used in endoscopicsurgery. The rod lens endoscope includes a very precise group of lensesin an elongate and rigid tube which are able to accurately transmit animage to a remote camera in line with the lens group. The rod lensendoscope, because of its cost of manufacture, failure rate, andrequirement to be housed within a rigid and straight housing, is beingincreasingly replaced by solid state imaging technology which enablesthe image sensor to be placed at the distal tip of the investigatingdevice. The three most common solid state image sensors include chargedcoupled devices (CCD), charge injection devices (CID) and photo diodearrays (PDA). In the mid-1980s, complementary metal oxide semiconductors(CMOS) were developed for industrial use. CMOS imaging devices offerimproved functionality and simplified system interfacing. Furthermore,many CMOS imagers can be manufactured at a fraction of the cost of othersolid state imaging technologies.

One particular advance in CMOS technology has been in the activepixel-type CMOS imagers which consist of randomly accessible pixels withan amplifier at each pixel site. One advantage of active pixel-typeimagers is that the amplifier placement results in lower noise levelsthan CCDs or other solid state imagers. Another major advantage is thatthese CMOS imagers can be mass produced on standard semiconductorproduction lines. One particularly notable advance in the area of CMOSimagers including active pixel-type arrays is the CMOS imager describedin U.S. Pat. No. 5,471,515 to Fossum, et al. This CMOS imager canincorporate a number of other different electronic controls that areusually found on multiple circuit boards of much larger size. Forexample, timing circuits, and special functions such as zoom and antijitter controls can be placed on the same circuit board containing theCMOS pixel array without significantly increasing the overall size ofthe host circuit board. Furthermore, this particular CMOS imagerrequires 100 times less power than a CCD-type imager. In short, the CMOSimager disclosed in Fossum, et al. has enabled the development of a“camera on a chip.”

Passive pixel-type CMOS imagers have also been improved so that they toocan be used in an imaging device which qualifies as a “camera on achip.” In short, the major difference between passive and active CMOSpixel arrays is that a passive pixel-type imager does not perform signalamplification at each pixel site. One example of a manufacturer whichhas developed a passive pixel array with performance nearly equal toknown active pixel devices and being compatible with the read outcircuitry disclosed in the U.S. Pat. No. 5,471,515 is VLSI Vision, Ltd.,1190 Saratoga Avenue, Suite 180, San Jose, Calif. 95129. A furtherdescription of this passive pixel device may be found in applicant'sU.S. Pat. No. 5,986,693 entitled “Reduced Area Imaging DevicesIncorporated Within Surgical Instruments,” which is hereby incorporatedby reference.

In addition to the active pixel-type CMOS imager which is disclosed inU.S. Pat. No. 5,471,515, there have been developments in the industryfor other solid state imagers which have resulted in the ability to havea “camera on a chip.” For example, Suni Microsystems, Inc. of MountainView, Calif., has developed a CCD/CMOS hybrid which combines the highquality image processing of CCDs with standard CMOS circuitryconstruction. In short, Suni Microsystems, Inc. has modified thestandard CMOS and CCD manufacturing processes to create a hybrid processproviding CCD components with their own substrate which is separate fromthe P well and N well substrates used by the CMOS components.Accordingly, the CCD and CMOS components of the hybrid may reside ondifferent regions of the same chip or wafer. Additionally, this hybridis able to run on a low power source (5 volts) which is normally notpossible on standard CCD imagers which require 10 to 30 volt powersupplies. A brief explanation of this CCD/CMOS hybrid can be found inthe article entitled “Startup Suni Bets on Integrated Process” found inElectronic News, Jan. 20, 1997 issue. This reference is herebyincorporated by reference for purposes of explaining this particulartype of imaging processor.

Another example of a recent development in solid state imaging is thedevelopment of a CMOS imaging sensor which is able to achieve analog todigital conversion on each of the pixels within the pixel array. Thistype of improved CMOS imager includes transistors at every pixel toprovide digital instead of analog output that enable the delivery ofdecoders and sense amplifiers much like standard memory chips. With thisnew technology, it may, therefore, be possible to manufacture a truedigital “camera on a chip.” This CMOS imager has been developed by aStanford University joint project and is headed by Professor Abbasel-Gamal.

A second approach to creating a CMOS-based digital imaging deviceincludes the use of an over-sample converter at each pixel with a onebit comparator placed at the edge of the pixel array instead ofperforming all of the analog to digital functions on the pixel. This newdesign technology has been called MOSAD (multiplexed over sample analogto digital) conversion. The result of this new process is low powerusage, along with the capability to achieve enhanced dynamic range,possibly up to 20 bits. This process has been developed by A mainElectronics of Simi Valley, Calif. A brief description of both of theprocesses developed by Stanford University and A main Electronics can befound in an article entitled “A/D Conversion Revolution for CMOSSensor?,” September 1998 issue of Advanced Imaging. This reference isalso hereby incorporated by reference for purposes of explaining theseparticular types of imaging processors.

The above-mentioned developments in solid state imaging technology haveshown that “camera on a chip” devices will continue to be enhanced notonly in terms of the quality of imaging which may be achieved, but alsoin the specific construction of the devices which may be manufactured bynew breakthrough processes.

Although the “camera on a chip” concept is one which has great merit forapplication in many industrial areas, a need still exists for a reducedarea imaging device which can be used in even the smallest type ofendoscopic instruments in order to view areas in the body that areparticularly difficult to access, and to further minimize patient traumaby an even smaller diameter invasive instrument.

It is one general object of this invention to provide a wirelessendoscope incorporating reduced area imaging devices which takeadvantage of “camera on a chip” technology, but rearrange the circuitryin a stacked relationship so that there is a minimum profile presentedwhen used within a surgical instrument or other investigative device. Itis another object of this invention to provide a wireless endoscopeutilizing low cost imaging devices which may be “disposable.” It is yetanother object of this invention to provide reduced area imaging devicescapable of wireless communications which may be used in conjunction withstandard endoscopes by placing the imaging device through channels whichnormally receive other surgical devices, or receive liquids or gases forflushing a surgical area. It is yet another object of this invention toprovide a surgical device with imaging capability which may be batterypowered and may wirelessly communicate for viewing video images.

In addition to the intended use of the wireless endoscope with respectto surgical procedures conducted by medical doctors, it is alsocontemplated that the invention described herein has great utility withrespect to oral surgery and general dental procedures wherein a verysmall imaging device can be used to provide an image of particularlydifficult to access locations. Additionally, while the foregoinginvention has application with respect to the medical and dental fields,it will also be appreciated by those skilled in the art that the smallsize of the imaging device set forth herein coupled with the wirelesscommunication feature can be applied to other functional disciplineswherein the imaging device can be used to view difficult to accesslocations for industrial equipment and the like. Therefore, the imagingdevice of this invention could be used to replace many industrialboroscopes.

The “camera on a chip” technology can be furthered improved with respectto reducing its profile area and incorporating such a reduced areaimaging device into very small investigative instruments which can beused in the medical, dental, or other industrial fields.

SUMMARY OF THE INVENTION

In accordance with the present invention, reduced area imaging devicesare provided. The term “imaging device” as used herein describes theimaging elements and processing circuitry which is used to produce avideo signal which may be accepted by a standard video device such as atelevision or video monitor accompanying a personal computer. The term“image sensor” as used herein describes the components of a solid stateimaging device which captures images and stores them within thestructure of each of the pixels in the array of pixels found in theimaging device. As further discussed below, the timing and controlcircuits can be placed either on the same planar structure as the pixelarray, in which case the image sensor can also be defined as anintegrated circuit, or the timing and control circuitry can be placedremote from the pixel array. The terms “signal” or “image signal” asused herein, and unless otherwise more specifically defined, refer to animage which at some point during its processing by the imaging device,is found in the form of electrons which have been placed in a specificformat or domain. The term “processing circuitry” as used herein refersto the electronic components within the imaging device which receive theimage signal from the image sensor and ultimately place the image signalin a usable format. The terms “timing and control circuits” or“circuitry” as used herein refer to the electronic components whichcontrol the release of the image signal from the pixel array.

In a first embodiment of the endoscope, the imaging device utilizeswired connections for interconnecting the various elements of theimaging device, and utilizes wired connections for transferring videoimages to a video display.

In a second embodiment of the endoscope, a wireless communications meansmay be used to allow various elements of the imaging device tocommunicate with one another. Transfer of video images to a videodisplay can also be achieved by the wireless communications means. Thusin the second embodiment, the endoscope does not have to be physicallyconnected to other operating room equipment which greatly enhances theease of using the wireless endoscope. Particularly in endoscopicprocedures which are conducted in hard to reach locations within thebody, a wireless endoscope is advantageous because there are no trailingcables or sterile drapes which otherwise complicate maneuvering of theendoscope. In general, enhanced maneuverability of the endoscope isprovided by the wireless communications.

One particularly advantageous wireless technology usable with theendoscope of this invention is known as “Bluetooth”. Another recentwireless technology which is usable with the invention is a wirelessprotocol known as “IEEE 802.15.13”. This wireless standard is developingunder the joint efforts of Kodak, Motorola, Cisco and the InternationalElectronic and Electrical Engineers Standards Association (IEEE)Wireless Personal Area Network Working Group (WPAN). Bluetoothtechnology provides a universal radio interface in the 2.4 GHz frequencyband that enables portable electronic devices to connect and communicatewirelessly via short-range ad hoc networks. Bluetooth radios operate inan unlicenced Instrumentation, Scientific, Medical (ISM) band at 2.4Ghz. Bluetooth is a combination of circuit and packet switching. Slotscan be reserved for synchronous packets. Each packet is transmitted in adifferent hop frequency. A packet nominally covers a single slot, butcan be extended to cover up to five slots. Bluetooth can support anasynchronous data channel, up to three simultaneous synchronous voicechannels, or a channel that simultaneously supports asynchronous dataand synchronous voice. Spectrum spreading is accomplished by frequencyhopping 79 hops displaced 1 MHZ starting at 2.402 Ghz and stopping at2.480 GHz. The maximum frequency hopping rate is 1600 hops per second.The nominal link range is 10 centimeters to 10 meters, but can beextended to more than 100 meters by increasing the transmit power. Ashaped binary FM modulation is applied to minimize transceivercomplexity. The gross data rate is 1 Mb/second. A time divisionmultiplex scheme is used for full-duplex transmission. Additionalinformation describing the Bluetooth global specification is found onthe world wide web at www.bluetooth.com. Additional informationregarding the technical specification for the IEEE 802.15.13 standardmay be found www.ieee802.org/15 under the link for the Task Force Three(TG3). The content of both of these websites is hereby incorporated byreference for purposes of disclosing these types of communicationstandards.

In a first arrangement of the imaging device, the image sensor, with orwithout the timing and control circuitry, may be placed at the distaltip of the endoscopic instrument while the remaining processingcircuitry may be found in a small remote control box which maywirelessly communicate with the image sensor.

In a second arrangement of the imaging device, the image sensor and theprocessing circuitry may all be placed in a stacked arrangement ofcircuit boards and positioned at the distal tip of the endoscopicinstrument. In this second arrangement, the pixel array of the imagesensor may be placed by itself on its own circuit board while the timingand control circuitry and processing circuitry are placed on one or moreother circuit boards. Alternatively, the circuitry for timing andcontrol may be placed with the pixel array on one circuit board, whilethe remaining processing circuitry can be placed on one or more of theother circuit boards.

In another alternative arrangement, the imaging device may be adaptedfor use with a standard rod lens endoscope wherein the imaging device isplaced within a standard camera housing which is configured to connectto a standard “C” or “V” mount connector.

In yet another arrangement, the timing and control circuitry and/or theprocessing circuitry may be placed in the handle of the endoscope. It iseven completed that some circuitry could be placed in the handle of theendoscope while remaining circuitry is placed within the remote controlbox. Because of the small size of the elements making up the imagingdevice coupled with the ability to provide wireless communicationsbetween the elements, great diversification is provided for thecombinations of locations at which the different elements may beemployed.

A simplified endoscope may be used which includes a very small diametertubular portion which is inserted within the patient. The tubularportion may be made of a flexible material having a central lumen oropening therein for receiving the elements of the imaging device. Thetubular portion may be modified to include an additional concentric tubeplaced within the central lumen and which enables a plurality of lightfibers to be placed circumferentially around the periphery of the distalend of the tubular portion. Additionally, control wires may extend alongthe tubular portion in order to make the endoscope steerable. Thematerial used to make the endoscope can be compatible with any desiredsterilization protocol, or the entire endoscope can be made sterile anddisposable after use.

In the second embodiment of the endoscope wherein processing circuitryis housed within the endoscope, and for the arrangement of the imagingdevice which calls for the array of pixels and the timing and controlcircuitry to be placed on the same circuit board, only one conductor isrequired in order to electrically transfer the image signal to theprocessing circuitry. In the other configuration of the imaging devicewherein the timing and control circuits are incorporated onto othercircuit boards, a plurality of connections are required in order toconnect the timing and control circuitry to the pixel array and the oneconductor is also required to transfer the image signal.

In each of the different arrangements of the imaging device wherecircuitry is housed in the handle of the endoscope, the handle can haveone or more channels or bores for making space available for suchcircuitry.

Thus, the wireless communications made integral with the endoscope ofthe second embodiment provides an improved endoscope wherein theimprovement comprises variations of wireless communications fortransmission of image signals that are viewed on a desired videodisplay.

In another aspect of the invention, the imaging device is housed withinan endoscopic instrument in which the endoscope is steerable byincorporating a steering connector assembly located near the imagingdevice. The connector assembly is constructed so that it does notenlarge the profile of the capsule that houses the imaging device, yetthe connector assembly facilitates precise and accurate control of thedistal end of the endoscope with a four-way deflection capability. Morespecifically, the image sensor has a frontal profile defined by a lengthand width dimension, and the connector assembly does not extend beyondthis frontal profile or a slightly larger frontal profile defined by thelength and width dimension of the capsule.

The connector assembly has dual functionality in providing a means toanchor the distal ends of the steering wires as well as to provide astructure for attaching the electrical leads of an image/power cable toelectrical traces housed in the connector assembly that extend toelectrically contact electrical connection points on the imaging device.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 a illustrates a first arrangement of the imaging device includinga fragmentary cross-sectional view of a generic endoscopic instrument inthe first embodiment, and a fragmentary perspective view of a controlbox, the endoscope and control box each incorporating elements of areduced area imaging device;

FIG. 1 b is an enlarged fragmentary partially exploded perspective viewof the distal end of the endoscopic instrument specifically illustratingthe arrangement of the image sensor with respect to the other elementsof the tubular portion of the endoscope;

FIG. 2 a is a fragmentary cross-sectional view of the endoscope in thefirst embodiment, and a second arrangement of the imaging device whereinthe imaging device is incorporated in its entirety at the distal tip ofthe endoscope;

FIG. 2 b is an enlarged fragmentary partially exploded perspective viewof the distal end of the endoscope of FIG. 2 a illustrating the imagingdevice;

FIG. 3 a is a fragmentary cross-sectional view of the image sensorincorporated with a standard camera housing for connection to a rod lensendoscope;

FIG. 3 b is a fragmentary cross-sectional view of the imaging deviceincorporated within the camera housing of FIG. 3 a;

FIG. 3 c is a fragmentary cross-sectional view similar to that of FIG. 3b illustrating a battery as an alternate source of power;

FIG. 4 is a schematic diagram of the functional electronic componentswhich make up the imaging device;

FIG. 4 a is an enlarged schematic diagram of a circuit board which mayinclude the array of pixels and the timing and control circuitry;

FIG. 4 b is an enlarged schematic diagram of a video processing boardhaving placed thereon the processing circuitry which processes thepre-video signal generated by the array of pixels and which converts thepre-video signal to a post-video signal which may be accepted by astandard video device;

FIGS. 5 a-5 e are schematic diagrams that illustrate an example ofspecific circuitry which may be used to make the imaging device.

FIG. 6 is a fragmentary cross-sectional view of an endoscope in thesecond embodiment wherein image signals in a desired video ready formatare wirelessly transmitted to a remote video display monitor for viewingby a user;

FIG. 6 a is another fragmentary cross-sectional view of the endoscope ofFIG. 6 showing an alternate source of light in the form of a fiber opticcable connected to an external light source;

FIG. 6 b is another fragmentary cross-sectional view of the endoscope ofFIG. 6 showing processing circuitry incorporated within the handle ofthe endoscope as opposed to the circuitry placed within the tubularportion of the endoscope;

FIG. 7 illustrates a transceiver radio module which receives imagesignals transmitted by the wireless endoscope of FIG. 6. FIG. 6 a, andconditions the received image signals for direct reception by a displaymonitor;

FIG. 8 illustrates another endoscope of the second embodiment whereinsome image signal processing is conducted remote from the endoscope;

FIG. 8 a illustrates a removable battery housing which may be rechargedby removing the housing and plugging it into the recharge receptacle onthe control box of FIG. 9; and

FIG. 9 illustrates the arrangement of the imaging device whichincorporates the control box wherein image signals from the endoscope inFIG. 8 are in a first or pre-format and are transmitted wirelessly tothe control box, circuitry in the control box processes the imagesignals in a second or final format, and the control box then wirelesslytransmits the image signals to a secondary receiver which receives theimage signals and conditions the image signals for direct reception bythe display monitor.

FIG. 10 is a partially exploded fragmentary perspective view of anendoscopic instrument incorporating the imaging device of the presentinvention, along with a connector assembly to facilitate steering of theinstrument;

FIG. 11 is a greatly enlarged fragmentary perspective view of FIG. 10showing further details of the connector assembly;

FIG. 12 is another greatly enlarged fragmentary perspective viewillustrating details of the connector assembly; and

FIG. 13 is a fragmentary perspective view illustrating the endoscopicinstrument connected to a conventional steering device enabling preciseand accurate steering of the distal tip of the endoscopic instrument.

BEST MODE FOR CARRYING OUT THE INVENTION

In accordance with one arrangement of the imaging device as shown inFIG. 1 a, an endoscope 10 in the first embodiment is provided whichincorporates a reduced area imaging device 11, shown in FIG. 1 b. Asfurther discussed below, the elements of the imaging device may all befound at one location or the elements may be separated from one anotherand interconnected by the appropriate cable(s). The array of pixelsmaking up the image sensor captures images and stores them in the formof electrical energy by conversion of light photons to electrons. Thisconversion takes place by the photo diodes in each pixel whichcommunicate with one or more capacitors which store the electrons. Thestructure of the endoscope 10 in the first embodiment includes aflexible or rigid tubular portion 14 which is inserted into the body ofthe patient and is placed at the appropriate location for viewing adesired surgical area. The tubular portion 14 attaches at its proximalend to a handle portion 12 which may be grasped by a surgeon who isconducting the endoscopic procedure. The handle 12 may include a centrallumen or channel 13 which receives one or more cables or otherstructures which extend to the distal end 16 of tubular portion 14.Handle portion 12 may further include a supplementary channel 15 whichintersects with central channel 13 and which may provide another pointof entry for other cables, fluids or operative instruments to be placedthrough the endoscope.

FIG. 1 b illustrates the distal end of the endoscope 16. The distal end16 may be characterized by an outer tube 18 which traverses the lengthof the tubular portion 14 and connects to the handle portion 12. Placedconcentrically within the outer tube 18 may be one or more inner tubes20. In FIG. 1 b, the gap between inner tube 20 and outer tube 18 forms aspace in which one or more light fibers 22 or control wires 24 may beplaced. As well understood by those skilled in the art, a plurality ofcircumferentially spaced light fibers as illustrated in FIG. 1 b can beused to illuminate the surgical site. Additionally, the control wires 24may communicate with a control mechanism (not shown) integrated on thehandle portion 12 for manipulating the distal end 16 of the endoscope ina desired direction. The flexible tubular portion 14 coupled with asteerable feature enables the endoscope to be placed within windingbodily passages or other locations difficult to reach within the body.

An image sensor 40 may be placed within the central channel defined byinner tube 20. In the configuration shown in FIG. 1 b, a cable 26 isused to house the conductors which communicate with the image sensor 40.An intermediate support tube 28 may be placed concentrically outside ofcable 26 and concentrically within inner tube 20 to provide thenecessary support for the cable 26 as it traverses through the innerchannel defined by inner tube 20. In lieu of support tube 28, otherwell-known means may be provided to stabilize the cable 26 such as clipsor other fastening means which may attach to the inner concentricsurface of inner tube 20.

A control box 30 may be placed remote from the endoscope 10. The controlbox 30 contains some of the processing circuitry which is used toprocess the image signal produced by image sensor 40. Therefore, theimaging device 11 as previously defined would include the processingcircuitry within control box 30 and the image sensor 40 located at thedistal tip of the endoscope. Control box 30 communicates with imagesensor 40 by means of cable 32 which may simply be an insulated andshielded cable which houses therein cable 26. Cable 32 is stabilizedwith respect to the handle portion 12 by means of a fitting 34 whichensures that cable 32 cannot be inadvertently pushed or pulled withinchannel 13. Additionally, an additional fitting 35 may be provided tostabilize the entry of a light cable 36 which houses the plurality oflight fibers 22. Light cable 36 runs along cable 32 to the distal end ofthe endoscope, or light cable 36 can join cable 32 within the channel 13as shown in FIG. 1 a. Thus cable 32 would house both the light fibersand the conductors which interconnect the control box 30 to the imagesensor 40.

Image sensor 40 is illustrated as being a planar and square shapedmember. However, the image sensor may be modified to be in a planar andcircular shape to better fit within the channel defined by inner tube20. Accordingly, FIG. 1 b further shows an alternate shaped image sensor40′ which is round. A lens group or system 42 may be incorporated at thedistal end of the endoscope in order to manipulate the image prior to itbeing impinged upon the array of pixels on the image sensor 40. Thislens system 42 may be sealed at the distal end 16 of the endoscope sothat the tubular portion 14 is impervious to fluids entering through thedistal end 16. In the configuration of the imaging device 11 in FIGS. 1a and 1 b, there are only three conductors which are necessary forproviding power to the image sensor 40, and for transmitting an imagefrom the image sensor 40 back to the processing circuitry found withincontrol box 30. Namely, there is a power conductor 44, a groundingconductor 46, and an image signal conductor 48 each of which are hardwired to the image sensor. Thus, cable 26 may simply be athree-conductor 50 ohm cable.

Image sensor 40 can be as small as 1 mm in its largest dimension.However, a more preferable size for most endoscopic procedures woulddictate that the image sensor 40 be between 4 mm to 8 mm in its largestdimension. The image signal electrically transmitted from the imagesensor through conductor 48 is also herein referred to as a pre-videosignal. Once the pre-video signal has been electrically transmitted fromimage sensor 40 by means of conductor 48, it is received by videoprocessing board 50. Video processing board 50 then carries out all thenecessary conditioning of the pre-video signal and places it in a formso that it may be viewed directly on a standard video device, televisionor standard computer video monitor. The signal produced by the videoprocessing board 50 can be further defined as a post-video signal whichcan be accepted by a standard video device. As shown in FIG. 1 a, aconductor 49 is provided which electrically transmits the post-videosignal to an output connector 58 on the exterior surface of control box30. The cable (not shown) extending from the desired video device (notshown) may receive the post-video signal by means of connector 58. Powersupply board 52 may convert incoming power received through power source54 into the desired voltage. In the preferred imager incorporated inthis invention, the power to the imaging device is simply a directcurrent which can be a 1.5 volt to a 12 volt source. Incoming powerfrom, for example, a wall receptacle, communicates with power supplyboard 52 by connector 56. Power supply board 52 takes the incoming powersource and regulates it to the desired level. Additionally, ground 46 isalso shown as extending back to the source of power through connector56.

FIG. 2 a illustrates a second arrangement of the imaging device whereinthe imaging device is self-contained entirely within the distal end 16of the endoscope, and a power source which drives the circuitry withinthe imaging device may come from a battery 66 housed within handleportion 12.

As shown in FIG. 2 b, the video processing board 50 may be placeddirectly behind image sensor 40. A plurality of pin connectors 62 serveto electrically couple image sensor 40 with video processing board 50depending upon the specific configuration of image sensor 40, pinconnectors 62 may be provided either for structural support only, or toprovide a means by which image signals are electrically transmittedbetween image sensor 40 and board 50. When necessary, one or moresupplementary boards 60 may be provided which further contain processingcircuitry to process the image signal and present it in a form which maybe directly received by a desired video device. The area which isoccupied by image sensor 40 may be defined as the profile area of theimaging device and which determines its critical dimensions. Any imagingelements that are found on boards 50 or 60 must be able to be placed onone or more circuit boards which are longitudinally aligned with imagesensor 40 along longitudinal axis XX. If the profile area is notcritical in terms of limiting the largest sized imaging element withinthe imaging device, then the additional circuit boards 50 and 60 whichare normally placed in line with image sensor 40 can be aligned in anoffset manner or may be larger than the profile area of image sensor 40.In the configuration of FIG. 2 b, it is desirable that elements 40, 50and 60 be approximately the same size so that they may fit uniformlywithin the central channel of the endoscope. Additionally, image sensor40 may be bonded to lens system 42 in order to provide furtherstructural support to the imaging device 11 when mounted within thedistal end 16.

Referring back to the handle portion 12 in FIG. 2 a, an additionalchannel 64 may be provided in order that a power supply cable 68 maycommunicate with battery 66. Conveniently, battery 66 may itself bemounted within a well 65 formed in handle portion 12. Cable 68 carriesthe conductor 44 and ground 46. Cable 68 may intersect with cable 33within channel 13, cables 68 and 33 extending then to the distal end 16.Cable 33 can be a single conductor cable which transmits the post-videosignal to a desired video device. In other words, cable 33 may simply bean insulated and shielded housing for conductor 49 which carries thepost-video signal. Because a preferred image sensor of the imagingdevice 11 may only require a 5 volt power supply, a battery is an idealpower source in lieu of a conductor which would trail the endoscope.Accordingly, the endoscope is made more mobile and easier to handle byeliminating at least one of the trailing cables.

FIG. 3 a illustrates yet another arrangement or configuration of theimaging device wherein the imaging device can be used in conjunctionwith a standard rod lens endoscope 70.

As shown, rod lens endoscope 70 includes a lens train 72 which includesa plurality of highly precise lenses (not shown) which are able totransmit an image from the distal end of the endoscope, to a camera inline with the endoscope. The rod lens endoscope is equipped with a lightguide coupling post 74. Light guide post 74 connects to a source oflight in the form of a cable 77 having a plurality of fiber opticstrands (not shown) which communicate with a source of light (notshown). The most common arrangement of the rod lens endoscope alsoincludes a “C” or “V” mount connector 78 which attaches to the eyepiece76. The “C” or “V” mount attaches at its other end to a camera group 80.The camera group 80 houses one or more of the elements of the imagingdevice. In this configuration, the small size of the imaging device isnot a critical concern since the imaging device is not being placed atthe distal end of the endoscope.

However, the incorporation of the imaging device in a housing whichwould normally hold a traditional camera still provides an advantageousarrangement. As shown, the camera group 80 may include a housing 82which connects to a power/video cable 86. Fitting 87 is provided tocouple cable 86 to the interior elements of the camera group 80 foundwithin housing 82. FIG. 3 a illustrates an arrangement of the imagingdevice 11 wherein the image sensor 40 is placed by itself within thehousing 82 and the processing circuitry of the imaging device can bepositioned in a remote control box as shown in FIG. 1 a. Accordingly,only three conductors 44, 46 and 48 are necessary for providing power tothe image sensor 40 and for transmitting the pre-video signal to thecontrol box. Alternatively, as shown in FIG. 3 b, the entire imagingdevice 11 may be incorporated within camera group 80, each of theelements of the imaging device being placed in the stacked arrangementsimilar to FIG. 2 b. As discussed above, size is not as much of aconcern in the embodiment of FIGS. 3 a and 3 b since the camera grouphousing 82 is much larger than the distal tip of the endoscope of FIGS.1 a and 2 a.

FIG. 3 c also illustrates the use of a battery 66 which provides sourceof power to the imaging device in either FIG. 3 a or 3 b. In thisarrangement, housing 82 is altered to include a battery housing 69 whichhouses the battery 66 therein. Battery housing 69 may include a verysmall diameter channel which may allow conductor 48 or 49 to communicatedirectly with the processing circuitry or video device, respectively. Itwill also be understood that the embodiment in FIG. 1 a may incorporatethe use of a battery 66 as the source of power. Thus, handle 12 in FIG.1 a may be altered in the same way as housing 82 to allow a battery tobe attached to the handle portion 12.

In all of the arrangements of the imaging device discussed above withrespect to the first embodiment of the endoscope, each of the elementsor components of the imaging device electrically communicate with oneanother through a wired connection.

FIG. 4 is a schematic diagram illustrating one way in which the imagingdevice 11 may be constructed. As illustrated, the image sensor 40 mayinclude the timing and control circuits on the same planar structure.Power is supplied to image sensor 40 by power supply board 52. Theconnection between image sensor 40 and board 52 may simply be a cablehaving two conductors therein, one for ground and another fortransmitting the desired voltage. These are illustrated as conductors 44and 46. The output from image sensor 40 in the form of the pre-videosignal is input to video processor board 50 by means of the conductor48. In the configuration of FIG. 4, conductor 48 may simply be a 50 ohmconductor. Power and ground also are supplied to video processing board50 by conductors 44 and 46 from power supply board 52. The output signalfrom the video processor board 50 is in the form of the post-videosignal and which may be carried by conductor 49 which can also be a 50ohm conductor.

In the first arrangement of the imaging device illustrated in FIG. 1 a,cable 32 can be used to house conductors 44, 46 and 48. In thearrangement shown in FIG. 2 a, cable 33 can be used to house conductor49 by itself when a battery power source is used, or alternatively,cable 33 may house conductors 44, 46 and 49 if the arrangement of FIG. 2a utilizes a power source from board 52.

Optionally, a supplementary processing board 60 may be provided tofurther enhance the pre-video signal. As shown in FIG. 4, thesupplementary board 60 may be placed such that the pre-video signal fromimage sensor 40 is first sent to the supplementary board and then outputto the video processor board 50. In this case, the output from board 50can be carried along conductor 51. This output can be defined as anenhanced pre-video signal. Furthermore, the post-video signal from videoprocessor board 50 may return to the supplementary board 60 for furtherprocessing, as further discussed below. The conductor used toelectrically transmit the post-video signal back to the supplementaryboard is shown as conductor 59. The power supply board 52 may alsoprovide power to the supplementary board in the same manner as to imagesensor 40 and board 50. That is, a simple hard-wired connection is madeonto the supplementary board for the ground and voltage carryingconductors. As discussed above, image sensor 40 may be placed remotelyfrom boards 50 and 60. Alternatively, image sensor 40, and boards 50 and60 each may be placed within the distal end of the endoscope.

Although FIG. 4 illustrates the image sensor and the timing and controlcircuits being placed on the same planar structure, it is possible toseparate the timing and control circuits from the pixel array and placethe timing and control circuits onto video processing board 50. Theadvantage in placing the timing and control circuits on the same planarstructure as the image sensor is that only three connections arerequired between image sensor 40 and the rest of the imaging device,namely, conductors 44, 46 and 48. Additionally, placing the timing andcontrol circuits on the same planar structure with the pixel arrayresults in the pre-video signal having less noise. Furthermore, theaddition of the timing and control circuits to the same planar structurecarrying the image sensor only adds a negligible amount of size to onedimension of the planar structure. If the pixel array is to be the onlyelement on the planar structure, then additional connections must bemade between the planar structure and the video processing board 50 inorder to transmit the clock signals and other control signals to thepixel array. For example, a ribbon-type cable (not shown) or a pluralityof 50 ohm coaxial cables (not shown) must be used in order to controlthe downloading of information from the pixel array. Each of theseadditional connections would be hard wired between the boards.

FIG. 4 a is a more detailed schematic diagram of image sensor 40 whichcontains an array of pixels 90 and the timing and control circuits 92.One example of a pixel array 90 which can be used within the inventionis similar to that which is disclosed in U.S. Pat. No. 5,471,515 toFossum, et al., said patent being incorporated by reference herein. Morespecifically, FIG. 3 of Fossum, et al. illustrates the circuitry whichmakes up each pixel in the array of pixels 90. The array of pixels 90 asdescribed in Fossum, et al. is an active pixel group with intra-pixelcharged transfer. The image sensor made by the array of pixels is formedas a monolithic complementary metal oxide semiconductor integratedcircuit which may be manufactured in an industry standard complementarymetal oxide semiconductor process. The integrated circuit includes afocal plane array of pixel cells, each one of the cells including aphoto gate overlying the substrate for accumulating the photo generatedcharges. In broader terms, as well understood by those skilled in theart, an image impinges upon the array of pixels, the image being in theform of photons which strike the photo diodes in the array of pixels.The photo diodes or photo detectors convert the photons into electricalenergy or electrons which are stored in capacitors found in each pixelcircuit. Each pixel circuit has its own amplifier which is controlled bythe timing and control circuitry discussed below. The information orelectrons stored in the capacitors is unloaded in the desired sequenceand at a desired frequency, and then sent to the video processing board50 for further processing.

Although the active pixel array disclosed in U.S. Patent No. 5,471,515is mentioned herein, it will be understood that the hybrid CCD/CMOSdescribed above, or any other solid state imaging device may be usedwherein timing and control circuits can be placed either on the sameplanar structure with the pixel array, or may be separated and placedremotely. Furthermore, it will be clearly understood that the inventionclaimed herein is not specifically limited to an image sensor asdisclosed in the U.S. Pat. No. 5,471,515, but encompasses any imagesensor which may be configured for use in conjunction with the otherprocessing circuitry which makes up the imaging device of thisinvention.

The timing and control circuits 92 are used to control the release ofthe image information or image signal stored in the pixel array. In theimage sensor of Fossum, et al., the pixels are arranged in a pluralityof rows and columns. The image information from each of the pixels isfirst consolidated in a row by row fashion, and is then downloaded fromone or more columns which contain the consolidated information from therows. As shown in FIG. 4 a, the control of information consolidated fromthe rows is achieved by latches 94, counter 96, and decoder 98. Theoperation of the latches, counter and decoder is similar to theoperation of similar control circuitry found in other imaging devices.That is, a latch is a means of controlling the flow of electrons fromeach individual addressed pixel in the array of pixels. When a latch 94is enabled, it will allow the transfer of electrons to the decoder 98.The counter 96 is programmed to count a discrete amount of informationbased upon a clock input from the timing and control circuits 92. Whenthe counter 96 has reached its set point or overflows, the imageinformation is allowed to pass through the latches 94 and be sent to thedecoder 98 which places the consolidated information in a serial format.Once the decoder 98 has decoded the information and placed it in theserial format, then the row driver 100 accounts for the serialinformation from each row and enables each row to be downloaded by thecolumn or columns. In short, the latches 94 will initially allow theinformation stored in each pixel to be accessed. The counter 96 thencontrols the amount of information flow based upon a desired timesequence. Once the counter has reached its set point, the decoder 98then knows to take the information and place it in the serial format.The whole process is repeated, based upon the timing sequence that isprogrammed. When the row driver 100 has accounted for each of the rows,the row driver reads out each of the rows at the desired video rate.

The information released from the column or columns is also controlledby a series of latches 102, a counter 104 and a decoder 106. As with theinformation from the rows, the column information is also placed in aserial format which may then be sent to the video processing board 50.This serial format of column information is the pre-video signal carriedby conductor 48. The column signal conditioner 108 places the columnserial information in a manageable format in the form of desired voltagelevels. In other words, the column signal conditioner 108 only acceptsdesired voltages from the downloaded column(s).

The clock input to the timing and control circuits 92 may simply be aquartz crystal timer. This clock input is divided into many otherfrequencies for use by the various counters. The run input to the timingand control circuit 92 may simply be an on/off control. The defaultinput can allow one to input the pre-video signal to a video processorboard which may run at a frequency of other than 30 hertz. The datainput controls functions such as zoom. At least for a CMOS type activepixel array which can be accessed in a random manner, features such aszoom are easily manipulated by addressing only those pixels which locatea desired area of interest by the surgeon.

A further discussion of the timing and control circuitry which may beused in conjunction with an active pixel array is disclosed in U.S. Pat.No. 5,471,515 and is also described in an article entitled “Active PixelImage Sensor Integrated With Readout Circuits” appearing in NASA TechBriefs, October 1996, pp. 38 and 39. This particular article is alsoincorporated by reference.

Once image sensor 40 has created the pre-video signal, it is sent to thevideo processing board 50 for further processing. At board 50, as shownin FIG. 4 b, the pre-video signal is passed through a series of filters.One common filter arrangement may include two low pass filters 114 and116, and a band pass filter 112. The band pass filter only passes lowfrequency components of the signal. Once these low frequency componentspass, they are then sent to detector 120 and white balance circuit 124,the white balance circuit distinguishing between the colors of red andblue. The white balance circuit helps the imaging device set its normal,which is white. The portion of the signal passing through low passfilter 114 then travels through gain control 118 which reduces themagnitude or amplitude of this portion to a manageable level. The outputfrom gain control 118 is then fed back to the white balance circuit 124.The portion of the signal traveling through filter 116 is placed throughthe processor 122. In the processor 122, the portion of the signalcarrying the luminance or non-chroma is separated and sent to the Ychroma mixer 132. Any chroma portion of the signal is held in processor122.

Referring to the output of the white balance circuit 124, this chromaportion of the signal is sent to a delay line 126 where the signal isthen further reduced by switch 128. The output of switch 128 is sentthrough a balanced modulator 130 and also to the Y chroma mixer 132where the processed chroma portion of the signal is mixed with theprocessed non-chroma portion. Finally, the output from the Y chromamixer 132 is sent to the NTSC/PAL encoder 134, commonly known in the artas a “composite” encoder. The composite frequencies are added to thesignal leaving the Y chroma mixer 132 in encoder 134 to produce thepost-video signal which may be accepted by a television or other videodisplay device.

Referring back to FIG. 4, it further illustrates supplementary board 60which may be used to digitally enhance or otherwise further conditionthe pre-video signal produced from image sensor 40. For example, digitalenhancement can brighten or otherwise clarify the edges of an imageviewed on a video screen. Additionally, the background images may beremoved thus leaving only the foreground images or vice versa. Theconnection between image sensor 40 and board 60 may simply be theconductor 48 which may also transfer the pre-video signal to board 50.Once the pre-video signal has been digitally enhanced on supplementaryboard 60, it is then sent to the video processor board 50 by means ofanother conductor 51. The pre-video signal is an analog signal. Thedigitally enhanced pre-video signal may either be a digital signal or itmay be converted back to the analog domain prior to being sent to board50.

In addition to digital enhancement, supplementary board 60 may furtherinclude other circuitry which may further condition the post-videosignal so that it may be viewed in a desired format other than NTSC/PAL.As shown in FIGS. 4, intermediate conductor 59 may transmit the signaloutput from Y chroma mixer 132 back to the supplementary board 60 wherethe signal is further encoded for viewing in a particular format. Onecommon encoder which can be used includes an RGB encoder 154. The RGBencoder separates the signal into three separate colors (red, green andblue) so that the surgeon may selectively choose to view only thoseimages containing one or more of the colors. Particularly in tissueanalysis where dyes are used to color the tissue, the RGB encoder mayhelp the surgeon to identify targeted tissue.

The next encoder illustrated in FIG. 4 is a SVHS encoder 156 (supervideo home system). This encoder splits or separates the luminanceportion of the signal and the chroma portion of the signal prior toentering the video device. Some observers believe that a cleaner signalis input to the video device by such a separation which in turn resultsin a more clear video image viewed on the video device. The last encoderillustrated in FIG. 4 is a VGA encoder 158 which enables the signal tobe viewed on a standard VGA monitor which is common to many computermonitors.

One difference between the arrangement of image sensor 40 and theoutputs found in FIG. 3 of the Fossum, et al. patent is that in lieu ofproviding two analog outputs [namely, VS out (signal) and VR out(reset)], the reset function takes place in the timing and controlcircuitry 92. Accordingly, the pre-video signal only requires oneconductor 48.

FIGS. 5 a-5 e illustrate in more detail one example of circuitry whichmay be used in the video processing board 50 in order to produce apost-video signal which may be directly accepted by a video device suchas a television. The circuitry disclosed in FIGS. 5 a-5 e is verysimilar to circuitry which is found in a miniature quarter-inchPanasonic camera, Model KS-162. It will be understood by those skilledin the art that the particular arrangement of elements found in FIGS. 5a-5 e are only exemplary of the type of video processing circuitry whichmay be incorporated in order to take the pre-video signal and conditionit to be received by a desired video device.

As shown in FIG. 5 a, 5 volt power is provided along with a ground byconductors 44 and 46 to board 50. The pre-video signal carried byconductor 48 is buffered at buffer 137 and then is transferred toamplifying group 138. Amplifying group 138 amplifies the signal to ausable level as well as achieving impedance matching for the remainingcircuitry.

The next major element is the automatic gain control 140 shown in FIG. 5b. Automatic gain control 140 automatically controls the signal fromamplifying group 138 to an acceptable level and also adds othercharacteristics to the signal as discussed below. More specifically,automatic gain control 140 conditions the signal based upon inputs froma 12 channel digital to analog converter 141. Converter 141 retrievesstored information from EEPROM (electrically erasable programmable readonly memory) 143. EEPROM 143 is a non-volatile memory element which maystore user information, for example, settings for color, tint, balanceand the like. Thus, automatic gain control 140 changes the texture orvisual characteristics based upon user inputs. The signal leaving theautomatic gain control 140 is an analog signal until being converted byanalog to digital converter 142.

Digital signal processor 144 of FIG. 5 c further processes the convertedsignal into a serial type digital signal. One function of themicroprocessor 146 is to control the manner in which digital signalprocessor 144 sorts the digital signals emanating from converter 142.Microprocessor 146 also controls analog to digital converter 142 interms of when it is activated, when it accepts data, when to releasedata, and the rate at which data should be released. Microprocessor 146may also control other functions of the imaging device such as whitebalance. The microprocessor 146 may selectively receive the informationstored in the EEPROM 143 and carry out its various commands to furthercontrol the other elements within the circuitry.

After the signal is processed by digital signal processor 144, thesignal is sent to digital encoder 148 illustrated in FIG. 5 d. Some ofthe more important functions of digital encoder 148 are to encode thedigital signal with synchronization, modulated chroma, blanking,horizontal drive, and the other components necessary so that the signalmay be placed in a condition for reception by a video device such as atelevision monitor. As also illustrated in FIG. 5 d, once the signal haspassed through digital encoder 148, the signal is reconverted into ananalog signal through digital to analog converter 150.

This reconverted analog signal is then buffered at buffers 151 and thensent to amplifier group 152 of FIG. 5 e which amplifies the signal sothat it is readily accepted by a desired video device. Specifically, asshown in FIG. 5 e, one SVHS outlet is provided at 160, and two compositeor NTSC outlets are provided at 162 and 164, respectively.

Now turning to a discussion of the endoscope of the second embodiment,attention is first directed to FIG. 6. In this second embodiment, likereference numerals denote matching elements from the endoscope of thefirst embodiment. The endoscope of the second embodiment also can becharacterized as a common or generic endoscope except for the imagingdevice and 2 0 the wireless communications means incorporated in thissecond embodiment. FIG. 6 more specifically illustrates the arrangementof the imaging device wherein processing of the image signals isconducted within the endoscope such that a post-video signal is readyfor transmission to a display monitor. As shown, video processing board50 is mounted adjacent the image sensor 40 in the distal tip of theendoscope. As discussed above, one or more supplementary 2 5 boards 60may also be mounted adjacent the video processing board 50 for furtherprocessing of the image signals to produce a post-video signal of adesired format. Alternatively, and as further discussed below, some orall of the processing circuitry may be mounted within the handle 12, ina specified portion of the channel 13. There is ample room withinchannel 13, or some other bore which could be formed in the handle toreceive processing circuitry. The construction of the distal tip of theendoscope in the second embodiment can be the same as in the firstembodiment. Thus, steering wires (not shown) and circumferentiallyspaced light fibers (not shown) may be incorporated in the endoscope.Cable 32 carrying the post-video signals electrically connects to atransceiver radio element 170 which is housed within channel 13 towardsthe proximal end of the handle 12. Transceiver radio element 170conditions the post video signals in accordance with the desiredwireless standard. More specifically, the transceiver radio element addsa high frequency carrier signal and baseband protocol to the post videosignals, and then wirelessly transmits the post video signals viaantennae 174 to the transceiver radio module 178. The transceiver radiomodule 178 authenticates the received signals, strips the signals of thecarrier frequency, and then routs the signals in the final video formatto a display monitor 196. It should also be understand that thecommunications between the transceiver radio element 170 and thetransceiver radio module 178 are not simply one-way communications;rather, the communications are two way in accordance with the Bluetoothstandard or IEEE standard. For example, not only does the transceiverradio element 170 transmit image signals, but the transceiver radioelement 170 also receives and processes authentication signals from theradio transceiver module 178. Similarly, not only does the transceiverradio module 178 receive and process image signals, but the module 178also transmits authentication signals. A power switch (not shown) mayalso be incorporated within the endoscope to selectively energize orde-energize the image sensor 40 and the transceiver radio element 170.

Transceiver radio module 178 receives the post-video signals viaantennae 180, decodes the signals, and then electrically transmits themto the monitor 196 for viewing by the user. The endoscope in this secondembodiment is powered by a battery 176 which is housed adjacent theantennae 174. Electrical leads (not shown) extend from the battery 176to power the image 2 5 sensor and the transceiver radio element 170. Asdiscussed further below, antennae 174 and battery 176 may be securedwithin their own casing or housing 172 which then connects to the handle12 of the endoscope. Transceiver radio module 178 may simply be poweredby the same electrical power source (not shown) which powers the displaymonitor 196, such as conventional 110 volt, 3 phase power. In order torecharge the battery 176 of the endoscope, the transceiver radio modulemay be a combination unit which also has a battery charge circuit 182for recharging battery 176. Charge circuit 182 would also be powered bya conventional power source, preferably the same power source poweringthe transceiver module 178 and the display monitor 196. Circuit 182would have a charging receptacle, shown schematically as receptacle 186,for receiving the battery 176. FIG. 6 also shows a self-contained whitelight source in the form of light source 192 which is housed in channel15 between interior plug 194 and exterior plug or access cover 195.Alternatively, as shown in FIG. 6 a, an exterior source of light 198could be used which transmits light through the cable 36. The selfcontained light source 192 is preferred because the endoscope is thenfree from all trailing cables or other wiring.

FIG. 6 b illustrates the endoscope having another cavity or opening 210formed therein for housing some or all of the processing circuitry. Asshown, the video processor board 50 has been moved to the opening 210and is supported in the opening by support 212 which is placed in theopening 210 at a selected depth to accommodate the particular sizedcircuitry placed in the opening. Conductor 214 interconnects the board50 with image sensor 40, and conductor 214 can run coterminously withcable 32. Accordingly, the only imaging device element remaining in thedistal end of the endoscope is the image sensor 40. Additionally, thetiming and control circuits 92 could also be placed in the opening 210along with the video processing circuitry. The co-pending applicationSer. No. 09/368,246 is also incorporated herein by reference forpurposes of disclosing circuitry placed in the handle of the endoscope.

FIGS. 8 and 9 illustrate another arrangement of the imaging deviceincorporated within the endoscope of the second embodiment. In preface,FIGS. 8 and 9 illustrate the arrangement in which some elements of theimaging device are placed within the endoscope, and remaining elementsof the imaging device are placed within the control box 30. Wirelesstransmission of image signals takes place between the endoscope and thecontrol box. Final transmission of the post-video signal can then beconducted either electrically through a cable interconnecting thedisplay monitor and the control box, or final transmission may takeplace via another wireless transmission of the post-video signal fromthe control box to the display monitor.

Referring first to FIG. 8, the endoscope is shown which is identical tothe endoscope shown in FIG. 6 with the exception that there is no videoprocessor board 50 or other associated video processing circuitry housedwithin the endoscope. Thus, the transceiver radio element 170 receives apre-video signal form the image sensor 40, and then wirelessly transmitsthe pre-video signal to the control box 30. The transceiver radio module178 receives the pre-video signal and transfers the same to videoprocessor board 50. Video processor board 50 alone or in conjunctionwith other processing circuitry such as a supplementary processing board60 (not shown) places the image signal in a post-video format for directreception by the display monitor 196. Additionally, it is alsocontemplated that the timing and control circuitry 92 could be placed inthe control box 30. In such a case, the transceiver radio module 178would not only transmit authentication signals, but also signalsgenerated from the timing and control circuitry 92 for controlling theimage sensor 40.

In lieu of a camera battery charge circuit incorporated within a unitwhich is co-located with the display monitor as shown in FIG. 7, thecharge circuit 182 may be housed within the control box 30. Accordingly,circuit 182 could be powered by power supply board 52. Additionally, acamera power switch 184 could be included within control box 30 toselectively energize or de-energize the video processor board and itsfunction in converting pre-video signals to post-video signals. As inthe endoscope of FIG. 6, the endoscope of FIG. 8 could also have its ownpower switch (not shown) to energize or de-energize functioning of theimaging elements and the transceiver radio module 170.

FIG. 9 also illustrates a secondary communications scheme whereby thepost video signals could be wirelessly transmitted to the displaymonitor 196. Optionally, video processor board 50 (or other processingcircuitry) could electrically communicate with a secondary RFtransmitter 200 which would transmit the post-video signals via antennae202. These post-video signals would then be received via antennae 206 bya secondary RF receiver 204 mounted adjacent the display monitor 196.For this secondary transmission, Bluetooth could be used; however, itwould be preferable to use a different transmission standard between theprimary and the secondary communications to prevent potentialinterference. One example of a secondary RF transmitter which could beused is an rf-video transmitter model no. SDX-22, manufactured byRF-Video.com of Toronto, Canada. This type of transmitter also operatesin the 2.4 GHz frequency, and provides 80 mW of RF power. An example ofan acceptable secondary RF receiver which could be used is an rf-videoreceiver model no. VRX-24 also manufactured by RF-Video.com. This typeof receiver has an adjustable frequency of 2.2 to 2.7 Ghz.

FIG. 8 a illustrates that the battery 176 may be removed from theendoscope for recharge. As shown, housing 172 carries both the antennae174 and the battery 176; however, it shall be understood that thehousing 176 could alternatively only carry the battery 176, while theantennae 174 could be housed within channel 13 of the endoscope. Onepractical reason for placing antennae 174 within housing 172 is that theantennae is more easily replaced if it is located within a removableelement. The distal end of the housing 172 is received within well orbore 208 in the endoscope. Well 208 could be threaded to match externalthreads on the distal end of the housing 172, or other means such as aclip or a friction fit could be used as understood by those skilled inthe art in order to connect housing 172 to the endoscope. Similarly, theproximal end of the housing 172 could be threaded or otherwise adaptedso that the proximal end of the housing 172 could be received byreceptacle 186 for recharge of the battery 176. As yet another optionfor recharge of the battery 176, a recharge cable 188 includingrespective fittings/connectors 190 at each end of the cable 188 could beused to interconnect battery 176 with receptacle 186. Thus if cable 188were used, housing 172 could remain attached to the endoscope. Onesituation which might lend itself for use of cable 188 would be ifbattery 176 became discharged to the point where it failed or was indanger of failing to provide enough potential to the image sensor andtransceiver radio element during a surgical procedure. Cable 188 couldthen be used to provide instantaneous power to the endoscope.

Referring to FIGS. 10-12, in another aspect of the present invention, asteering connector assembly is provided in combination with the imagingdevice to provide a steering capability for the endoscope withoutincreasing the size of the profile for the endoscopic device. One commonprior art method of incorporating a steering capability involves the useof externally mounted steering wires and a yoke or bracket that isfitted over the distal end of the endoscope. The use of an externallymounted steering device greatly enlarges the front profile of theendoscope, and thereby prevents use of the endoscope in small passagesor cavities within the body. Additionally, externally mounted steeringdevices can complicate overall maneuverability of the endoscope byfurther limiting the flexibility of the endoscope. The connectorassembly of the present invention provides a fully contained orinternally isolated steering capability that avoids these disadvantagesof the prior art. Referring to the FIGS. 10-12, an endoscopic device isillustrated including a steering connector assembly 300 thatinterconnects a CMOS camera module 302 with the body of the endoscopicdevice. A polymer jacket 304 houses the camera elements shown in phantomlines. The endoscopic device includes one or more flexible distal bodyportions 306 that may articulate or bend based upon control of thesteering wires 310 that extend through passages formed in the sheath ofthe endoscope. Preferably, the steering wires 310 run through the jacketor sheath of the endoscopic device from the proximal end as shown inFIG. 10 to the distal end as shown in FIGS. 11 and 12. The endoscopicdevice may also include a more rigid proximal body portion 308 thatconnects to a steering assembly 340 as shown in FIG. 13.

Referring to FIG. 11, details of the steering connector assembly 300 areshown. The connector assembly includes a connector body or base 320 thatmay be a molded piece characterized by a plurality of transverse orlaterally extending flanges 324 interconnected by an orthogonallyextending center member 325. The connector body 320 provides gaps orspaces in which electrical traces 322 may be housed. The electricaltraces 322 electrically interconnect the CMOS imager 316 to theelectrical wires 315 of the image/power cable 314, as also shown in FIG.12. The distal end of the connector body 320 includes an imager supportbase 318 that is used to mount the CMOS imager 316. The electricaltraces 322 therefore also extend through the mount 318 and connect tothe various electrical pins or connections (not shown) of the imager316. The proximal end of the body 320 has a smaller width dimensiondefined by a pair of cutouts or notches formed on opposite lateral sidesof the proximal end. A strain relief member or cap 326 is mounted overthe proximal end of the body 320 at the location of the notches. Thestrain relief member 326 serves to protect the electrical traces 322,and also serves as the anchoring point for the distal ends of thesteering wires 310. As shown, the strain relief member 326 may be twochannel shaped elements that attach to the opposite lateral sides of thebody 320 at its proximal end. The exterior lateral edges of the member326 are substantially planer with the exterior lateral edges of thedistal end of the body 320. As illustrated, the distal ends 328 of thesteering wires 310 may be embedded within the facing surface of thestrain relief member 326, and the steering wires then extend proximallythrough the sheath of the distal body portion 306 of the endoscopicdevice. As illustrated, four steering wires are arranged in arectangular arrangement and located at corners of the rectangulararrangement. The strain relief member 326 as mounted results in afrontal profile for the connector assembly 300 that does not extendbeyond the frontal profile of the imaging device or the capsule 302. Asshown in FIG. 11, the upper surface of the strain relief member 326 ismounted over the upper surface of the body 320, and this arrangement isalso repeated with respect to the lower surface of the member 326.Therefore, the strain relief member extends slightly beyond the upperand lower surfaces of the body 320. The imaging device 316 has aslightly larger frontal profile than that of the distal end of the body320, so the strain relief member can be incorporated to not extendbeyond the profile of the imaging device since the thickness of thestrain relief elements are very small. Therefore, the strain reliefmember fits easily within the jacket 304 of the capsule 302 and thecapsule size does not have to be enlarged.

Also referring to FIG. 12, in the reverse perspective view, a pluralityof openings 330 can be seen that are formed through the sheath toreceive the steering wires 310. The image/power cable 314 is alsoillustrated that houses the plurality of wires 315. These wires 315carry the power and electronic signals to and from the CMOS imager. Forclarity, FIG. 11 does not show the electrical cable 314 and wires 315.In use, the distal ends of the wires 315 (not shown) are anchored in thegaps between the flanges 324, and these wires make contact with theelectrical traces 322 that also extend through the gaps 324.

Referring to FIG. 13, the endoscopic device is illustrated as connectedto a conventional steering assembly 340 that is used to facilitate anumber of functions for the endoscopic device, to include steering ofthe endoscopic device and the introduction of various fluids orinstruments through the endoscopic device. Accordingly, the steeringassembly 340 is illustrated with conventional controls, to include,steering controls 342 which can tension or loosen the wires to effect adesired articulation of the distal end of the endoscope. For example,one of the knobs/dials can control transverse movement while the otherknob/dial can control longitudinal movement. The FIG. 13 also showsother conventional controls such as frame and shutter controls 344 forthe imaging device, and various ports to receive gas, fluids and/orinstruments. For example, the FIG. 13 shows a suction port 346, an airport 348, an auxiliary port 350, and a biopsy port 352. The ports 350and 352 may receive instruments for conducting the desired surgicalprocedure, such as forceps, electrodes, etc.

The connector assembly 300 provides a structure for anchoring steeringwires and for stabilizing and supporting electrical connections betweenthe imaging device and the image/power cable. The connector assemblyfacilitates a steering capability but does not enlarge the frontalprofile of the imaging device since the steering wires are housed withinthe sheath of the endoscope and are anchored internally within thedistal end of the endoscope. Accordingly, the imaging device ismaintained in a very small configuration which provides great advantagesin terms of reducing the invasive nature of surgical procedures, as wellas providing additional options for use of the imaging device to besteered into an optimal location for imaging difficult to accesslocations within a body. Additionally, the location at which thesteering wires are anchored, namely, at the connector assembly itself,allows for optimum control in which the distal end of the endoscopicdevice can be maneuvered. In summary, the connector assembly fulfillstwo distinct purposes, namely, providing strain relief and support tothe electrical traces and electrical wires, and serving to anchor thedistal ends of the steering wires. The steering capability provided isusable with any of the imaging embodiments disclosed herein, to includeboth wired and wireless imaging capabilities.

From the foregoing, it is apparent that an entire imaging device may beincorporated within the distal tip of an endoscope, or may have someelements of the imaging device being placed in a small remote boxadjacent to the endoscope. Based upon the type of image sensor used, theprofile area of the imaging device may be made small enough to be placedinto an endoscope which has a very small diameter tube. Additionally,the imaging device may be placed into the channels of existingendoscopes to provide additional imaging capability without increasingthe size of the endoscope. The imaging device may be powered by astandard power input connection in the form of a power cord, or a smallbattery may be used. In order to enhance the freedom of using theendoscope without trailing cables, the endoscope may include wirelesstransmission capabilities. A wireless endoscope also has advantages withrespect to overall surgical efficiency in conducting procedures byminimizing requirements to drape or shield cables in the sterile field,and by providing an endoscope which has unlimited movement capabilitieswithout having to orient or otherwise handle the endoscope to accountfor twisted cables, drapes, or other components which are normallyassociated with endoscopic devices. A wireless transmission ofpost-video signals from the endoscope directly to the video display canbe done to provide video images. Alternatively, the imaging device canbe separated into components which are located in the endoscope and in aremote control box. Pre-video signals are wirelessly transmitted to thecontrol box, and then post-video signals are provided to the videodisplay either through a secondary wireless transmission, or by aconventional hard wired connection.

This invention has been described in detail with reference to particularembodiments thereof, but it will be understood that various othermodifications can be effected within the spirit and scope of thisinvention.

1. An imaging device comprising: a housing; an image sensor mounted insaid housing, said image sensor including a first circuit board having alength and a width thereto, wherein said length and width of said firstcircuit board define a first plane, said first circuit board includingan array of CMOS pixels thereon, wherein a plurality of CMOS pixelswithin said array of CMOS pixels each include an amplifier, said firstcircuit board further including timing and control circuitry thereon,said timing and control circuitry being coupled to said array of CMOSpixels, said image sensor producing a pre-video signal; a second circuitboard mounted in said housing, said second circuit board beingelectrically coupled to said first circuit board, said second circuitboard having a length and a width thereto, wherein said length and widthof said second circuit board define a second plane, said second circuitboard including circuitry thereon to convert said pre-video signal to apost-video signal, said second circuit board being offset from saidfirst circuit board, said second plane of said second circuit boardbeing substantially parallel to said first plane of said first circuitboard; a lens mounted in said housing, said lens being integral withsaid imaging device, said lens focusing images on said array of CMOSpixels of said image sensor; a video screen, said video screen beingelectrically coupled to said second circuit board, said video screenreceiving said post-video signal and displaying images from saidpost-video signal; and a power supply mounted in said housing, saidpower supply being electrically coupled to said first circuit board toprovide power to said array of CMOS pixels and said timing and controlcircuitry, said power supply also being electrically coupled to saidsecond circuit board to provide power thereto.
 2. The imaging device ofclaim 1, wherein: said image sensor has a generally square shape alongsaid first plane.
 3. The imaging device of claim 1, wherein: a largestdimension of said image sensor along said first plane is between 4 and 8millimeters.
 4. The imaging device of claim 1, wherein: a largestdimension of said second circuit board along said second plane isgreater than a largest dimension of said image sensor along said firstplane.
 5. The imaging device of claim 1, wherein: power provided by saidpower supply is direct current between 1.5 and 12 volts.
 6. The imagingdevice of claim 1, wherein: said power supply is a battery.
 7. Animaging device comprising: a housing; an image sensor mounted in saidhousing, said image sensor including a first circuit board having alength and a width thereto, wherein said length and width of said firstcircuit board define a first plane, said first circuit board includingan array of CMOS pixels thereon, wherein a plurality of CMOS pixelswithin said array of CMOS pixels each include an amplifier, said firstcircuit board further including timing and control circuitry thereon,said timing and control circuitry being coupled to said array of CMOSpixels, said image sensor producing a pre-video signal; a second circuitboard mounted in said housing, said second circuit board beingelectrically coupled to said first circuit board, said second circuitboard having a length and a width thereto, wherein said length and widthof said second circuit board define a second plane, said second circuitboard including circuitry thereon to convert said pre-video signal to apost-video signal, said second circuit board being positioned in astacked arrangement with respect to said first circuit board, saidsecond plane of said second circuit board being substantially parallelto said first plane of said first circuit board; a lens mounted in saidhousing, said lens being integral with said imaging device, said lensfocusing images on said array of CMOS pixels of said image sensor; avideo screen, said video screen being electrically coupled to saidsecond circuit board, said video screen receiving said post-video signaland displaying images from said post-video signal; and a power supplymounted in said housing, said power supply being electrically coupled tosaid first circuit board to provide power to said array of CMOS pixelsand said timing and control circuitry, said power supply also beingelectrically coupled to said second circuit board to provide powerthereto.
 8. The imaging device of claim 7, wherein: said image sensorhas a generally square shape along said first plane.
 9. The imagingdevice of claim 7, wherein: a largest dimension of said image sensoralong said first plane is between 4 and 8 millimeters.
 10. The imagingdevice of claim 7, wherein: a largest dimension of said second circuitboard along said second plane is greater than a largest dimension ofsaid image sensor along said first plane.
 11. The imaging device ofclaim 7, wherein: power provided by said power supply is direct currentbetween 1.5 and 12 volts.
 12. The imaging device of claim 7, wherein:said power supply is a battery.
 13. An imaging device comprising: ahousing; an image sensor mounted in said housing, said image sensorincluding a planar substrate having a length and a width thereto,wherein said length and width of said planar substrate define a firstplane, said planar substrate including an array of CMOS pixels thereon,wherein a plurality of CMOS pixels within said array of CMOS pixels eachinclude an amplifier, said image sensor further including a firstcircuit board having a length and a width thereto, wherein said lengthand width of said first circuit board define a second plane, said firstcircuit board including timing and control circuitry thereon, saidtiming and control circuitry being coupled to said array of CMOS pixels,said first circuit board being positioned in a stacked arrangement withrespect to said planar substrate, said second plane of said firstcircuit board being substantially parallel to said first plane of saidplanar substrate, said image sensor producing a pre-video signal; asecond circuit board mounted in said housing, said second circuit boardbeing electrically coupled to said planar substrate and to said firstcircuit board, said second circuit board having a length and a widththereto, wherein said length and width of said second circuit boarddefine a third plane, said second circuit board including circuitrythereon to convert said pre-video signal to a post-video signal, saidsecond circuit board being offset from said first circuit board and fromsaid planar substrate, said third plane of said second circuit boardbeing substantially parallel to said second plane of said first circuitboard and to said first plane of said planar substrate; a lens mountedin said housing, said lens being integral with said imaging device, saidlens focusing images on said array of CMOS pixels of said image sensor;a video screen, said video screen being electrically coupled to saidsecond circuit board, said video screen receiving said post-video signaland displaying images from said post-video signal; and a power supplymounted said housing, said power supply being electrically coupled tosaid planar substrate to provide power to said array of CMOS pixels,said power supply also being electrically coupled to said first circuitboard to provide power to said timing and control circuitry, said powersupply also being electrically coupled to said second circuit board toprovide power thereto.
 14. The imaging device of claim 13, wherein: saidimage sensor has a generally square shape along said first plane. 15.The imaging device of claim 13, wherein: a largest dimension of saidimage sensor along said first plane is between 4 and 8 millimeters. 16.The imaging device of claim 13, wherein: a largest dimension of saidsecond circuit board along said third plane is greater than a largestdimension of said image sensor along said first plane.
 17. The imagingdevice of claim 13, wherein: power provided by said power supply isdirect current between 1.5 and 12 volts.
 18. The imaging device of claim13, wherein: said power supply is a battery.
 19. An imaging devicecomprising: a housing; an image sensor mounted in said housing, saidimage sensor including a planar substrate having a length and a widththereto, wherein said length and width of said planar substrate define afirst plane, said planar substrate including an array of CMOS pixelsthereon, wherein a plurality of CMOS pixels within said array of CMOSpixels each include an amplifier, said image sensor further including afirst circuit board having a length and a width thereto, wherein saidlength and width of said first circuit board define a second plane, saidfirst circuit board including timing and control circuitry thereon, saidtiming and control circuitry being coupled to said array of CMOS pixels,said first circuit board being positioned in a stacked arrangement withrespect to said planar substrate, said second plane of said firstcircuit board being substantially parallel to said first plane of saidplanar substrate, said image sensor producing a pre-video signal; asecond circuit board mounted in said housing, said second circuit boardbeing electrically coupled to said planar substrate and to said firstcircuit board, said second circuit board having a length and a widththereto, wherein said length and width of said second circuit boarddefine a third plane, said second circuit board including circuitrythereon to convert said pre-video signal to a post-video signal, saidsecond circuit board being positioned in a stacked arrangement withrespect to said first circuit board and further with respect to saidplanar substrate, said third plane of said second circuit board beingsubstantially parallel to said second plane of said first circuit boardand to said first plane of said planar substrate; a lens mounted in saidhousing, said lens being integral with said imaging device, said lensfocusing images on said array of CMOS pixels of said image sensor; avideo screen, said video screen being electrically coupled to saidsecond circuit board, said video screen receiving said post-video signaland displaying images from said post-video signal; and a power supplymounted said housing, said power supply being electrically coupled tosaid planar substrate to provide power to said array of CMOS pixels,said power supply also being electrically coupled to said first circuitboard to provide power to said timing and control circuitry, said powersupply also being electrically coupled to said second circuit board toprovide power thereto.
 20. The imaging device of claim 19, wherein: saidimage sensor has a generally square shape along said first plane. 21.The imaging device of claim 19, wherein: a largest dimension of saidimage sensor along said first plane is between 4 and 8 millimeters. 22.The imaging device of claim 19, wherein: a largest dimension of saidsecond circuit board along said third plane is greater than a largestdimension of said image sensor along said first plane.
 23. The imagingdevice of claim 19, wherein: power provided by said power supply isdirect current between 1.5 and 12 volts.
 24. The imaging device of claim19, wherein: said power supply is a battery.
 25. An imaging devicecomprising: a housing; an image sensor mounted in said housing, saidimage sensor including a planar substrate having a length and a widththereto, wherein said length and width of said planar substrate define afirst plane, said planar substrate including an array of CMOS pixelsthereon, wherein a plurality of CMOS pixels within said array of CMOSpixels each include an amplifier, said planar substrate furtherincluding timing and control circuitry thereon, said timing and controlcircuitry being coupled to said array of CMOS pixels, said image sensorproducing a pre-video signal; a circuit board mounted in said housing,said circuit board being electrically coupled to said planar substrate,said circuit board having a length and a width thereto, wherein saidlength and width of said circuit board define a second plane, saidcircuit board including circuitry thereon to convert said pre-videosignal to a post-video signal, said circuit board being offset from saidplanar substrate, said second plane of said circuit board beingsubstantially parallel to said first plane of said planar substrate; alens mounted in said housing, said lens being integral with said imagingdevice, said lens focusing images on said array of CMOS pixels of saidimage sensor; a video screen, said video screen being electricallycoupled to said circuit board, said video screen receiving saidpost-video signal and displaying images from said post-video signal; anda power supply mounted in said housing, said power supply beingelectrically coupled to said planar substrate to provide power to saidarray of CMOS pixels and said timing and control circuitry, said powersupply also being electrically coupled to said circuit board to providepower thereto.
 26. The imaging device of claim 25, wherein: said imagesensor has a generally square shape along said first plane.
 27. Theimaging device of claim 25, wherein: a largest dimension of said imagesensor along said first plane is between 4 and 8 millimeters.
 28. Theimaging device of claim 25, wherein: a largest dimension of said circuitboard along said second plane is greater than a largest dimension ofsaid image sensor along said first plane.
 29. The imaging device ofclaim 25, wherein: power provided by said power supply is direct currentbetween 1.5 and 12 volts.
 30. The imaging device of claim 25, wherein:said power supply is a battery.
 31. An imaging device comprising: ahousing; an image sensor mounted in said housing, said image sensorincluding a planar substrate having a length and a width thereto,wherein said length and width of said planar substrate define a firstplane, said planar substrate including an array of CMOS pixels thereon,wherein a plurality of CMOS pixels within said array of CMOS pixels eachinclude an amplifier, said planar substrate further including timing andcontrol circuitry thereon, said timing and control circuitry beingcoupled to said array of CMOS pixels, said image sensor producing apre-video signal; a circuit board mounted in said housing, said circuitboard being electrically coupled to said planar substrate, said circuitboard having a length and a width thereto, wherein said length and widthof said circuit board define a second plane, said circuit boardincluding circuitry thereon to convert said pre-video signal to apost-video signal, said circuit board being positioned in a stackedarrangement with respect to said planar substrate, said second plane ofsaid circuit board being substantially parallel to said first plane ofsaid planar substrate; a lens mounted in said housing, said lens beingintegral with said imaging device, said lens focusing images on saidarray of CMOS pixels of said image sensor; a video screen, said videoscreen being electrically coupled to said circuit board, said videoscreen receiving said post-video signal and displaying images from saidpost-video signal; and a power supply mounted in said housing, saidpower supply being electrically coupled to said planar substrate toprovide power to said array of CMOS pixels and said timing and controlcircuitry, said power supply also being electrically coupled to saidcircuit board to provide power thereto.
 32. The imaging device of claim31, wherein: said image sensor has a generally square shape along saidfirst plane.
 33. The imaging device of claim 31, wherein: a largestdimension of said image sensor along said first plane is between 4 and 8millimeters.
 34. The imaging device of claim 31, wherein: a largestdimension of said circuit board along said second plane is greater thanthe largest dimension of said image sensor along said first plane. 35.The imaging device of claim 31, wherein: power provided by said powersupply is direct current between 1.5 and 12 volts.
 36. The imagingdevice of claim 31, wherein: said power supply is a battery.